Hitherto, with respect to a buckling stiffening brace member having an axial force member that is installed in a building structure and that absorbs the seismic energy at the time of earthquake, and a stiffening pipe that stiffens the axial force member, in order to increase the seismic energy absorbed by the axial force member, inventions for preventing total buckling of the axial force member and thereby achieving stable compressive and tensile plastic deformation have been made.
For example, Patent Literature 1 discloses a structural member that is formed by placing a steel pipe member outside a steel pipe member. The outer steel pipe member is formed by axially connecting several types of steel pipe members. End faces of the steel pipe members at axial ends are covered with end plates. Patent Literature 2 discloses a brace in which total buckling is prevented by filling a steel pipe member with mortar.